The present invention relates generally to special calling features for telephones, such as call screening, call forwarding, call waiting, etc. and, more particularly, to an adaptive call-screening method that automatically updates a call-screening database based on actions of the calling party and called party.
Modern telephone networks implementing automatic number identification (ANI) enable a called telephone to determine the number of a calling party and to take action based on the number. For example, some telephones enable the subscribing party to screen incoming telephone calls based on the caller ID number. The called party may elect to either accept or reject an incoming call based on the number of the calling party. Also, the called party may elect to divert calls from selected numbers to a recording device, such as a voice mail box or answering machine, for later retrieval by the called party.
When calls are diverted to a voice mail box or answering machine, they are presumably returned at a later date by the party who received the original call. If the original calling party, who is the called party on the return call, also uses call screening, the return call may be blocked or diverted to a voice mail box. This results in a state of xe2x80x9cperpetual telephone tagxe2x80x9d since both parties have calls from the other party screened.
Accordingly, there is a need for an adaptive call-screening method that avoids the telephone tag pitfall when the calling party and the called party each have calls from the other party screened.
The present invention is an adaptive call-screening method for use in a telephone having call-screening capability. According to the present invention, a call-screening database is stored in memory in the telephone. Incoming calls are accepted, rejected, or diverted to a recording device based on the entries in the call-screening database. The call-screening database is automatically updated in response to the placement of a call to a previously screened number when specified conditions are met so that calls can be received from the previously screened number. The updates to the call-screening database expire after a predetermined time period has elapsed. Also, the update may be cancelled once a return call is received.
In one embodiment of the invention, the call-screening database is updated when a call is placed to a number that is currently screened to temporarily accept incoming calls from such number. For example, if a user places a call to a number which is currently blocked or diverted by the calling party, the call-screening database is updated to place the number on an accept list. The update expires after a predetermined time period if no return call is made.
In another embodiment of the invention, the call-screening database is updated only when the calling party""s call is blocked or diverted at the receiving party""s end. The telephone automatically detects a beep tone indicative of an answering machine or voice mail system, or a systematic voice pattern indicative of a pre-recorded message. If a beep tone or pre-recorded message is detected, the call-screening database is updated so that any return call from the called party will be received. If the call is answered, no update is made to the call-screening database.
In another embodiment of the invention, the phone keeps a record of recently blocked or diverted calls. When the user places a call, the called number is compared to the numbers in the call record of recently blocked or diverted calls. If the called number matches one of the numbers in the call record of recently blocked or diverted calls, it is assumed that the user wants to accept calls from that number and the call-screening database is automatically updated. Again, the update expires after a predetermined time period, or upon the occurrence of predetermined conditions. Thus, calls will be temporarily received from the called party, whose prior calls had been blocked or diverted.
The present invention overcomes some of the pitfalls that might befall those who use sophisticated call-screening features. In particular, the present invention avoids the problem of creating a xe2x80x9cperpetual telephone tagxe2x80x9d situation by adaptively updating the call-screening database in the telephone, while preserving many of the advantages of advanced call-screening features.